Platen brake and paper blousing eliminator

ABSTRACT

A rod is rotatably and slidably mounted adjacent a rotatable platen. A continuous form fed past the platen engages both the platen and the rod causing the rod to slide toward and contact the platen. The form tends to rotate the platen clockwise while the rod being rotated clockwise by the form engages and tends to rotate the platen counterclockwise causing it to stop concurrent with cessation of form feed, particularly during high speed skip operations.

United States Patent 1191 Smith PLATEN BRAKE AND PAPER BLOUSING ELIMINATOR [75] Inventor: Jack E. Smith, Apalachin, NY.

[73] Assignee: lntemational Business Machines Corporation, Armonk, NY.

[22] Filed: June 12, 1972 [21] Appl. No.: 262,160

[52] u.s.c1. 197/133 11,226/59, 226/148 511 1111.01 B4lj 15/00 58 Field of Search 197/126 R, 127 R, 128,

197/133 R, 133 T, 133 F, 133 A, 133 P,.144, 145, 146, 147, 149, 138 R, 138 A; 226/59, 148, 195; l88/82.8, 82.84

[56] References Cited UNITED STATES PATENTS 1,105,853 8/1914 Shiek 197/127 R 2,419,759 4/1947 Briskin et al.. 226/59 1,870,197 8/1932 Sibley 226/148 2,270,730 l/l942 Gochnauer 226/148 [451 Mar. 26, 1974 3,161,277 12/1964 Smithbauer 197/133 R 1,152,944 9/1915 Harvey 197/18 1,665,444 4/1928 Chapman 197/133 R 1,957,203 5/1934 Eichenauer... 197/127 R 2,511,596 6/1950 Loughridge... 197/133 R 2,168,448 8/1939 Pitman 197/133 R X 3,519,117 7/1970 Smith 197/127 R Primary Examiner-Ernest T. Wright, Jr. Attorney, Agent, or Firm-Francis V. Giolma [5 7] ABSTRACT A rod is rotatably and slidably mounted adjacent a rotatableplaten. A continuous form fed past the platen engages both the platen and the rod causing the rod to slide toward and contact the platen. The form tends to rotate the platen clockwise while the rod being rotated clockwise by the form engages and tends to rotate the platen counterclockwise causing it to stop concurrent with cessation of form feed, particularly during high speed skip operations.

5 Claims, 2 Drawing Figures 1 PLATEN BRAKE AND PAPER BLOUSING ELIMINATOR FIELD OF THE INVENTION The invention relates generally to printers and it has reference in particular to braking of a rotatable platen in a continuous form printer.

DESCRIPTION OF THE PRIOR ART Spring members bearing against a form in the region of a platen have been used for braking the form in continuous form cutters and the like, as shown in U. S. Pat. No. 1,665,444, entitled Paper Feed and Cutting Mechanism, which issued Apr. 10, 1928, to S. E. Chapman.

' SUMMARY OF THE INVENTION Generally stated, it is an object of this invention to provide a simple and effective platen brake for a high speed printer.

More specifically, it is an object of the invention to provide for using a form actuated member engaging a rotatable platen to prevent overrun of the platen on high speed form skips.

Another object of the invention is to provide for preventing blousing of a form in a high speed skip operation'by using a movable brake rod-which is forced into engagement with a rotatable platen by the form.

Yet another object of the invention is to provide for having a continuous form slide a rotatable and slidable brake member into engagement with a rotatable platen which rotates with movement of the form for braking rotation of the platen.

The foregoing and other objects, features and advantages of the invention will be apparent from the following more detailed description of a preferred embodiment of the invention, as shown in the accompanying drawing.

DESCRIPTION .OF THE DRAWING In the drawing:

FIG. 1 is a schematic isometric view of a platen and brake construction for a printer embodying the invention in a preferred form; and I v I FIG. 2 is an enlarged partial cross-sectional view in elevation of the embodiment shown in FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to both FIGS. 1 and 2, the reference number denotes generally a platen of hard rubber, plastic or the like designed to be positioned behind a continuous Form 12, which is fed by means of a Tractor 14, for use with a printing mechanism such as the wire matrix print head shown in co-pending application Ser. No. 68,278 ofP. A. Brumbaugh et al, entitled Wire Matrix Print Head," filed August 31,; 1970 now Pat.

represented by the Leaf Spring 16, which is positioned onone side of the Document 12 and presses against a Support 18 on the other side, may be used to maintain tension in the Form or Document 12.

In order to provide a new print surface for each line of print, the Platen 10 is rotatably supported by means of a Shaft 20, which is mounted in Bearing Slots 2] in Support Arms 22 and 24at opposite ends of the Platen 'No. 3,672,482 issued June 27, 1972. A brake devic? 10, where it is retained by Caps 23. The Arms 22 and 24 may be pivotally mounted by means of a Shaft 26 and biased by means of Springs 28 against Cams 30 secured on a rotatable Shaft 32. The Shaft 32 may be rotated to rotate the Cams 30 and pivot the Arms 22 and 24 toward and away from the print mechanism to adjust for the maximum printing conditions with different thicknesses of Form 12. Means such as the Paw] 34, which is biased by means of a Spring 36 against a Star or Detent Wheel 38 on the Shaft 32, may be used to maintain the desired position of the Cams 30.

In order to prevent overrun of the Platen 10, which is rotated by frictional engagement with the Form 12, as it advances, and has a tendency to continue rotating after the Form 12 stops, brake means such as the Brake Rod 40 may be provided. The Brake Rod 40 may be rotatably and slidably supported by being positioned in Slots 42 in the Arms 22 and 24. Clips 44 secured to the Arms 22 and 24 retain the Rod 40 in the Slots 42. The Slots 42 are so positioned relative to the Platen 10 that the Form 12 engages the Brake Rod 40 as well as the Platen 10, causing the Brake Rod 40 and the Platen 10 to rotate in a clockwise direction as the Form 12 advances. The Form 12 also tends to move the Brake Rod 40 horizontally to the right, as shown in FIG. 2, causing it to engage with and wedge against the Platen 10. Frictional engagement between the Brake Rod 40 and the Platen 10 tends to cause the Platen 10 to rotate in a counterclockwise direction, which is opposite to the direction of rotation imparted to it by the Form 12. The result is that the position of the Platen 10 will change for each line of print as single line spacing occurs. In the case of high speed skips where the Form 12 advances several lines or more, the Rod 40 actually functions as a brake during advance of the Form 12, wedging against the Platen l0 and minimizing rotation of the Platen 10 to the extent that it stops turning after a relatively short advance of the Form 12, even though the Form 12 continues to advance, and is always stopped concurrent with or prior to cessation of movement of the Form 12. This prevents overrun of the Platen l0 and the creation of a blousing condition and/or slack condition in the Forms 12 which previously occurred with a free rotating platen, when the platen continued to rotate after the Paper Tractor l4 stopped, tending to drag the form with it.

From the above description and the accompanying drawing it will be seen that there is provided a simple platen brake and paper blousing eliminator which eliminates the problem of non-parallel printing and overlap printing between the first two lines of a print following a high speed skipping operation. The platen brake of the subject invention inhibits overrunning of the free rotating Platen 10, which is purposely made rotatable to provide a new printing surface for each line or print so as to minimize possibility of platen damage from the printing element. Movement of Forms 12 through the machine under tension and against the Platen 10 causes the Platen 10 to turn satisfactorily during normal spacing conditions. In a case of high speed skips of several inches the platen brake prevents rotation of the Platen 10 after the paper transport stops and prevents the tendency of the Platen 10 to drag the Form 12 with it, thus solving the problem.

While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. The combination with means for advancing a continuous form positioned on one side of a rotatable platen engaging and rotated by said continuous form to provide a backing for printing on the continuous form, said rotatable platen having a cylindrical periphery and coaxial ends, and means positioned on the other side of the rotatable platen to provide a drag and produce a tension in said continuous form, with said rotatable platen being so positioned as to provide a change in the direction of the path of said continuous form, between said means for advancing and said means for providing a drag, of

rotatable brake means slidably disposed away from and toward said rotatable platen to engage said rotatable platen at said periphery, said rotatable brake means being so positioned relative to said rotatable platen and said continuous form that the continuous form engages said rotatable brake means and said rotatable platen, rotating said rotatable brake means and forcing said rotatable brake means into engagement with said rotatable platen so as to tend to rotate said rotatable platen in the opposite direction to that in which said rotatable platen is rotated by said continuous form.

2. The invention as defined in claim 1 characterized by said rotatable platen being rotatably supported by spaced support means which support the ends of said rotatable platen, and said brake means comprising a cylindrical rotatable brake rod slidably disposed in slots having inner and outer ends in said support means to interfere with said rotatable platen.

3. The invention as defined in claim 2 characterized by said slots being off center and non-tangential with respect to said rotatable platen with said brake rod being substantially clear of said rotatable platen at the outer ends of said slots, and in engagement with said rotatable platen adjacent the inner ends of said slots.

4. The invention as defined in claim 3 characterized that said slots are horizontally disposed in said support means of said rotatable platen and are open at the outer ends and closed at the inner ends, and that said slots intersect the periphery of said rotatable platen adjacent said inner closed ends and are covered by clips at their outer ends.

5. The invention as defined in claim 4 characterized by said support means being pivotally supported and cam means operable to engage and actuate said support means to position said rotatable platen and brake rod in different operating positions. 

1. The combination with means for advancing a continuous form positioned on one side of a rotatable platen engaging and rotated by said continuous form to provide a backing for printing on the continuous form, said rotatable platen having a cylindrical periphery and coaxial ends, and means positioned on the other side of the rotatable platen to provide a drag and produce a tension in said continuous form, with said rotatable platen being so positioned as to provide a change in the direction of the path of said continuous form, between said means for advancing and said means for providing a drag, of rotatable brake means slidably disposed away from and toward said rotatable platen to engage said rotatable platen at said periphery, said rotatable brake means being so positioned relative to said rotatable platen and said continuous form that the continuous form engages said rotatable brake means and said rotatable platen, rotating said rotatable brake means and forcing said rotatable brake means into engagement with said rotatable platen so as to tend to rotate said rotatable platen in the opposite direction to that in which said rotatable platen is rotated by said continuous form.
 2. The invention as defined in claim 1 characterized by said rotatable platen being rotatably supported by spaced support means which support the ends of said rotatable platen, and said brake means comprising a cylindrical rotatable brake rod slidably disposed in slots having inner and outer ends in said support means to interfere with said rotatable platen.
 3. The invention as defined in claim 2 characterized by said slots being off center and non-tangential with respect to said rotatable platen with said brake rod being substantially clear of said rotatable platen at the outer ends of said slots, and in engagement with said rotatable platen adjacent the inner ends of said slots.
 4. The invention as defined in claim 3 characterized that said slots are horizontally disposed in said support means of said rotatable platen and are open at the outer ends and closed at the inner ends, and that said slots intersect the periphery of said rotatable platen adjacent said inner closed ends and are covered by clips at their outer ends.
 5. The invention as defined in claim 4 characterized by said support means being pivotally supported and cam means operable to engage and actuate said support means to position said rotatable platen and brake rod in different operating positions. 